Spabk-plto



S. H. HUGHES.

SPARK PLUG.

APPLICATION FILED iAN-24. 19x9.

' Patented Nov. 30, 1920.

I Jwunfin e5. HHuahea w Z1117! A UNITED STATES PATENT OFFICE.

SUGAR H. HUGHES, OF,OKMULGEE, OKLAHOMA.

SPARK-PLUG.

Specification of Letters Patent. Patented NOV. 30, 1920- Application filed January 24, 1919. Serial No. 272,829.-

To all whom it may concern:

Be it known that I, SUGAR HENRY HUGHES, a citizen of the United States, residing at Okmulgee, in the county of Okmulgee and State of Oklahoma, have invented certain new and useful Improvements in Spark- Plugs; and I do hereby declare the following to be a full, clear, and exact descri tion of the invention, such as will enab e others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in spark plugs and has for one of its objects the provision of means whereby the small and frail electrodes now frequently used can be dispensed with and a main electrode co operating with the body of a spark plug substituted or used in lieu thereof and which is in the form of a circular disk evenly spaced from the end of the body so as to produce an even and circular spark thereby insuring the correct ignition of the explosion charge of the engine at all times thus rendering a saving of fuel and reduce the carbonizing of the en inc.

Another object of t is invention is the provision of a spark plu of the above stated character, which shal be simple, durable and efficient, and which may be manufactured and sold at a comparatively low cost.

With these and other objects in View as will become more apparent as the descrip tion proceeds, the invention consists in certain novel features of construction, combination, and arrangement of parts, as will be hereinafter more fully described and claimed.

For a complete understanding of my in vention, reference is to be had to the following description, and accompanying drawing, in which Figure 1 is a side elevation of a spark plug constructed in accordance with my invention,

Fig. 2 is a vertical sectional view of the same,

Fig. 3 is a detail view of the electrode.

Referring in detail to the drawing, the numeral 1 indicates as an entirety the spark plug consisting of the body 2 provided with'the wrench engaging faces 3 and the formed therein an annular shoulder 5 on which is adapted to be seated a shoulder 6 formed upon an insulator 7. The shoulder 6 is formed upon the inner end of the insulator 7 while the outer end of the insulator is tapered. The insulator 7 is secured within the body 2 by means of the usual lock nut 8 that is threaded within the upper end of the body and bears against the shoulder 6 for forcing the same into engagement with the annular shoulder 5 establishing a leak proof connection between the insulator and the body. The insulator 7 is provided with a centrally arranged opening 10 which permits an electrode 11 to extend therethrough and which electrode projects beyond the lower end of the screw threaded extension 4 and has formed there on a disk or plate 12 of circular formation and which is relatively spaced from the end of theextension 4 of the body 2 so as to provide a spark gap. The electric current passing through electrode 11 into the plate 12 will jump from the same to the extension 4 of the body 2 in circular formation, thus rendering a comparatively large spark and an even one so as to assure the proper ignition of theexplosive charge of the engine at all times which reduces the carbonization of the engine as well as providing an even and smooth running engine.

The electrode 11 at a point below the insulator 7 has formed thereon an annular shoulder 13 adapted to support or limit the downward movement of disks 14E constructed of mica or other material suitable for the purpose. The disks 14 are adapted to be forced into engagement with the lower end of the insulator 7 by turning the nut 15 on the upper end of the electrode into tight engagement with the upper end of the electrode thus establishing a leak-proof connection between the insulator and the electrode 11.

From the'foreiqoing description taken in connection with the accompanying drawing,

it will be noted that the disk 12 will also the spirit and scope of the invention as claimed.

Having thus described my invention, what I claim is A spark plug comprising a body, aninternal annular shoulder formed in said body intermediate its ends, an insulator in the upper end of said body, an annular flange formed on the lower end of said insulator and'restingon the shoulder and engaging the wall of said body, a bushing threaded in said body and bearing against the flange to'force it against the shoulder, a central electrode extending through the insulator andbody, a disk secured to the lower end of the electrode and having its periphery flush with the outer wall of said body and -said disk being disposed in spaced relation to, the lower end of said body, a shoulder formed on the electrode and spaced from the 20 lower end of the insulator, and a plurality of insulating disks on said electrode between the insulator and the last named shoulder. In testimony whereof I afiix my signature 1n presence or" two witnesses. 

